1. Field of Invention
The current invention relates to security tags and more particularly, discloses an approach for incorporating EAS or RFID components into corrugated structures on which a capacitor strap, a chip strap, or an RFID chip can be electrically coupled to form the EAS or RFID security tag.
2. Description of Related Art
Tracking or detecting the presence or removal of retail items from an inventory or retail establishment comes under the venue of electronic article surveillance (EAS), which also now includes radio frequency identification (RFID). EAS or RFID detection is typically achieved by applying an EAS or RFID security tag to the item or its packaging and when these security tags are exposed to a predetermined electromagnetic field (e.g., pedestals located at a retail establishment exit), they activate to provide some type of alert and/or supply data to a receiver or other detector.
However, the application of the EAS or RFID security tag to the item or its packaging in the first instance can be expensive and wasteful of resources used to form the security tag. For example, EAS security tags, typically comprise a resonant circuit that utilize at least one coil and at least one capacitor that operate to resonate when exposed to a predetermined electromagnetic field (e.g., 8.2 MHz) to which the EAS tag is exposed. By way of example only, the coil and the capacitor are etched on a substrate whereby a multi-turn conductive trace (thereby forming the coil) terminates in a conductive trace pad which forms one plate of the capacitor. On the opposite side of the substrate another conductive trace pad is etched to form the second capacitor plate, while an electrical connection is made through the substrate from this second plate to the other end of the coil on the first side of the substrate. The non-conductive substrate then acts as a dielectric between the two conductive trace pads to form the capacitor. Thus, a resonant circuit is formed. Various different resonant tag products are commercially available and described in issued patents, for example, U.S. Pat. Nos. 5,172,461; 5,108,822; 4,835,524; 4,658,264; and 4,567,473 all describe and disclose electrical surveillance tag structures.
With particular regard to radio frequency identification (RFID) tags, RFID tags include an integrated circuit (IC) coupled to a resonant circuit as mentioned previously or coupled to an antenna (e.g., a dipole) which emits an information signal in response to a predetermined electromagnetic field (e.g., 13.56 MHz). Recently, the attachment of the IC has been accomplished by electrically-coupling conductive flanges or strips to respective IC contacts to form a “chip strap.” This chip strap is then electrically coupled to the resonant circuit or antenna. See for example U.S. Pat. No. 6,940,408 (Ferguson, et al.); U.S. Pat. No. 6,665,193 (Chung, et al.); U.S. Pat. No. 6,181,287 (Beigel); and U.S. Pat. No. 6,100,804 (Brady, et al.).
Security systems commonly operate at the pallet and carton levels by reading RFID and EAS tags placed on the pallets or cartons. Accordingly, the industry has sought ways to attach the tags to cartons by placing the tags outside or inside the carton. U.S. Pat. No. 6,667,092 discloses a corrugated structure having a first and second liner board with a corrugated medium sandwiched between the first and second liner boards and an RFID processor coupled between one of the liner boards and the corrugated medium. The RF processor is positioned on an inlet or label, which may also include an antenna. The corrugated structure is formed by providing a liner board in a corrugated medium, positioning an RF processor between the liner board and the corrugated medium, and affixing the liner board and corrugated medium together with the RF processor positioned therebetween. However, placing an RF processor between one of the liner boards and the corrugated medium adds stress to delicate RFID chips during the processing of the RFID-enabled corrugated structure. In addition, since the chips must be inserted into the corrugated structure before the boxes are formed, the location of the chips must be coordinated with the size of the boxes so as to ensure that each box receives its intended chip. There remains a need for efficiently providing or integrating a security tag with a corrugated structure that is reliable and effective.
Another approach for placing an RF structure on a corrugated structure is disclosed in pending U.S. patent application Ser. No. 11/457,890, entitled “RFID TAGS FOR PALLETS AND CARTONS AND SYSTEM FOR ATTACHING SAME”, invented by Thomas Clare and Andre Cote, which discloses a multi-step approach for installing an RFID tag onto a shipping article. The approach includes the steps of applying a conductive strip to the surface of a shipping article and attaching an RFID chip to the conductive strip. To prevent a short in the RFID chip, the chip includes a nonconductive fin extending from the body of the chip and adapted to create a gap in the conductive strip between conductive bumps or barbs in the chip by puncturing through and splitting the conductive strip on opposite sides of the fin. It would still be beneficial to provide other approaches for integrating security tags with corrugated structures. All references cited herein are incorporated herein by reference in their entireties.